Posts tagged running
Which Running Gait Mechanics Predict Knee Injury?

With access to miles of paths and acres of open space running remains one of the most popular outdoor activities in Boulder. Despite its’ accessibility, low cost of participation, and health benefits running related injuries keep many from training or competing at their preferred levels. One recent area of research has focused on gait retraining by Physical Therapists to reduce forces among runners. Although an “ideal” running gait does not exist some factors including foot strike, impact forces, vertical translation can help us differentiate injured from non injured runners or determine who is at a greater risk of injury. A recent study determined additional factors which can help identify injured runners.

Dingenen and colleagues in the journal Physical Therapy in Sport analyzed the running gait of 42 recreational runners (2019). About half of the participants currently experienced pain on the front or side of their knee. Researchers assessed their lower quarter mechanics to determine how those with knee injuries differed from their non injured peers. Researchers found the injured runners demonstrated greater degrees of opposite sided pelvic drop and knee adduction (inward movement) during their running analysis. We often find these running gait impairments in runners with hip abductor (glut) weakness. Increased inward motion or “wag” of the knee in stance increases forces across the knee joint. Conversely, a level pelvis and stable knee helps dissipate the forces of running over a greater surface area in the joints.

Click Here to schedule your next running gait analysis with the experts at MEND

Which Muscle's Weakness Predicts Future Knee Pain?

Patellofemoral Pain Syndrome, pain under the knee cap, is the most common diagnosis of knee pain affecting both sedentary and active individuals. Muscle weakness in the hip and knee are often present in individuals with this diagnosis, but a cause and effect relationship between strength and knee pain has been difficult to established. In short, the research is divided on this relationship especially within the variable of hip weakness. Thus questions remain on which muscle imbalances may predispose an otherwise pain free individual for future patellofemoral pain.

A recent systematic review of the available evidence on the development of patellofemoral pain syndrome reviewed 18 studies of 4818 research participants (Neal et al. Br J Sp Med. 2019). Authors found three common groups of research subjects including military recruits, adolescents, and runners. They reported moderate to strong evidence body mass index, age, and leg alignment were not predictive of future knee pain. Interestingly, although common in clinical patients, moderate evidence reported hip weakness was not predictive of future knee pain. Authors reported quadricep weakness, especially among military recruits, was associated with future onset of knee pain.

Click Here to learn which exercises will help reduce your risk of future injury

What Is A Safe Weekly Running Progression?

Running remains one of the most popular forms of aerobic exercise due to its’ effectiveness and minimal equipment costs and entry fees. The majority of runners will sustain a running related injury at some point in their careers limiting their ability to train or compete. Training errors, increases in a runner’s volume (frequency, duration, terrain, intensity) too quickly over time, often contribute to the development of an overuse injury. Increasing running volume without adequate recovery prevents body tissues from positively adapting to the stress of exercise. A recent study documents what percentage increases in running volume are most associated with injury.

Damsted and colleagues in the Journal of Sports Physical Therapy studied 261 healthy runners over a 14 week period as they trained for an upcoming 1/2 marathon race (2018). 22% of the runners sustained a running related injury over the 14 week study period. Authors examined participants’ running volume increases and found those who increased their running volume > 20% per week sustained significantly more injures than those increasing their volume < 20% per week.

Do Compression Socks Help With Muscle Recovery?

Athletes have always sought remedies and treatments which accelerate their recovery from workouts. Optimal recovery allows for higher training intensities and in turn better performances during their sport of choice. Delayed onset muscle soreness (DOMS) is one of the most common reasons athletes struggle to reach a desired training intensity during a subsequent workout. Successful treatment approaches to reduce DOMS include a post workout cool down, nutrition, hydration, and foam rolling, but more recent attention has been focused on compression garments. These garments including leggings and socks are designed to optimize circulation across exercised muscles. Previous research has found no association between wearing a compression garments and improved performance, but there may be an effect on muscle soreness and recovery.

Heiss and colleagues examined the impact of compression socks on muscle performance, flexibility, circulatory markers, and recovery (JOSPT. 2018). Authors studied healthy young adults as they performed an exercise protocol designed to induce DOMS. Participants performed eccentric calf lowering using a weighted vest (25% of body weight) on an incline plane. They performed 5 sets of 30 reps with 10 seconds of rest between sets. After the exercise session, each participant immediately donned a compression sock on 1 randomized leg and wore the garment for 60 hours after the exercise session while the bare leg served as the control. Authors assessed muscle perfusion using contrast ultrasound and a MRI to assess muscular injury associated with DOMS. No effect of compression socks were found on circulation, flexibility, muscle soreness, calf circumference, or muscular injury. In contrast, authors did find a change in muscle stiffness between the legs depending on sock use.

This study supports our current understanding regarding compression socks. These garments remain an personal choice, but performance and recovery benefits remain inconclusive.

Is running volume or intensity more to blame for injury?

Running injuries remain a common problem for the vast majority of runners.  Many of these athletes report a loss of training days or competition due to a current or previous injury.  Contributing factors include muscle weakness, decreased mobility, and training errors.  Progressing training volumes (frequency, intensity, duration, terrain) too quickly prevent the tissues from properly adapting to the stresses of exercise.  A recent study examined if training intensity or training volume is more to blame for running related injuries.

A randomized controlled trial in the Journal of Orthopedic and Sports Physical Therapy was conducted to determine the impact of running intensity and running volume progression on future injury rates (Ramskov et al. 2018).  447 runners were randomized to one of two 16 week training programs after a combined 8 week preconditioning program.  The first group focused on intensity with runners training at > 88% of their VO2max.  The second group focused on running volume with progressive increases in training volume each week.   The authors reported 80 runners sustained an injury which kept them from completing the prescribed training sessions, but the authors found no difference in injury risk between the two groups. 



Will running worsen my knee arthritis?

Despite the amazing health benefits of exercise, the CDC estimates 80% of Americans do not meet national guidelines for weekly exercise.  Patients with knee arthritis report decreased participation in daily exercise programs including walking and moderate exercise secondary to pain, weakness, and fear of injury.  In our Boulder Physical Therapy practice many patients are fearful of exacerbating their current knee symptoms and restrict one of the most powerful interventions for their condition.  Exercise is critical to the successful management of knee arthritis and has been shown to have a protective effect on the joint's cartilage.  Many research studies have reported the absence of a link between running and development of arthritis, but does running worsen present arthritis?

A recent research study in the journal of Clinical Rheumatology examined the association between running and symptom and structural progression of knee arthritis (Lo et al. 2018).  1,203 runners included in the study were at least 50 years of age with radiographic evidence of arthritis in at least one knee.  Participants were examined at baseline and 4 years after entering the study.  Consistent with our current knowledge, running did not worsen the structural progression of arthritis.  The authors reported running was associated with a decrease in knee arthritis symptoms.  They concluded "self selected running need not be discouraged in people with knee osteoarthritis".  

Keep Fit